It is one of the most famous ideas in modern physics, but string theory is also strange and difficult to understand. Our guide should help you get started
D. Tong. (2009)cite arxiv:0908.0333
Comment: 210ish pages, lots of figures. These lectures were given in Part III
of the Mathematical Tripos at the University of Cambridge. Individual
chapters can be downloaded from
http://www.damtp.cam.ac.uk/user/tong/string.html . The notes on the course
webpage will be updated more frequently than those on the arXiv.